Titanium alloys have high relative strength and excellent corrosion resistance, and have mainly been used in the fields of aerospace, deep sea exploration, chemical plants, and the like. Recently, titanium alloys have been widely used for consumer uses such as heads or shafts of golf clubs, components of watches or fishing goods, and eyeglass frames.
Recently, composite materials containing a titanium alloy and carbon fiber combined for further improving mechanical properties such as tensile strength and toughness have been proposed. For example, Patent Documents 1 and 2 each disclose an automobile component formed of a titanium alloy containing carbon fibers such as carbon nanofibers. Patent Documents 1 and 2 each further describe injecting ions of oxygen (O), nitrogen (N), chlorine (Cl), chromium (Cr), carbon (C), boron (B), titanium (Ti), molybdenum (Mo), phosphorus (P), aluminum (Al), and the like into the carbon nanofibers, to thereby improve wetness and adhesiveness between the carbon nanofibers and metal. Further, pure titanium has also been cladded to a side surface of a core material made of a titanium alloy, for example, for obtaining functions and properties that cannot be obtained with a single substance (see Patent Document 3, for example).
Patent Document 1: JP 2004-225084
Patent Document 2: UP 2004-225765
Patent Document 3: JP 2002-000971